Uaru
Uaru amphiacanthoides
A large, relatively peaceful but highly gregarious South American cichlid. Often kept with Discus due to their shared need for very warm, pristine, acidic water. They are notorious herbivores that will devour almost any aquatic plant, and they actually require grazing on driftwood for proper digestion. They must be kept in groups.
Uaru At a Glance
Uaru Tank Requirements
Will Uaru fit in your tank?
Care guides tell you what Uaru needs, the next question is whether your tank can safely provide it. Test Uaru against your tank size, maintenance needs, and the fish you already keep before you buy.
Uaru Water Parameters
Uaru Temperament & Compatibility
Uaru Varieties
Each variety inherits the species defaults above. Only differences are highlighted.
Standard (Adult)
The adult form, distinguished by a silver/yellowish-brown body with a prominent, large dark wedge or teardrop shape on the flank. Very deep-bodied.
Differs in 1 trait from base species
Also known as: Adult Uaru, Triangle Cichlid
Juvenile (Grow-out)
Juveniles look completely different from adults, featuring dark mottling and spots designed to camouflage them in leaf litter. They grow rapidly and will quickly require a massive tank upgrade to accommodate their adult size and social group.
Differs in 5 traits from base species
Also known as: Baby Uaru, Spotted Uaru
Uaru Care Guide Summary
The Uaru, scientifically known as Uaru amphiacanthoides, belongs to the Cichlids - South American family group. Adults reach a maximum size of approximately 25 cm and have a compressed body shape with a moderate growth rate. Classified as mostly peaceful, this species primarily occupies the mid-level and bottom zones of the aquarium and produces a high level of biological waste.
To thrive, the Uaru requires a freshwater only aquarium with a minimum volume of 400 litres and a tank length of at least 150 cm. Water temperature should be maintained between 27°C and 30°C, with a pH range of 5–7 and a general hardness of 1–8 dGH. A low water flow is preferred.
The Uaru is a rewarding species to keep, provided its core environmental needs are met. This species is available in 2 varieties: Standard (Adult) and Juvenile (Grow-out). Each may differ slightly in size, temperament, or care needs, so it is worth checking the specific requirements of the variety you plan to keep.
Uaru Habitat Setup
When setting up an aquarium for the Uaru, a low water flow best suits their natural preferences. Because this species occupies the mid-level and bottom zones, the aquarium layout should prioritise open swimming space in the centre of the tank for free movement and sufficient floor space with hiding spots among rocks, wood, or dense planting. Useful additions include a sand substrate to accommodate their sifting behaviour and driftwood, which can serve as both a hiding place and a dietary supplement. Keepers should note that live planted layouts may be difficult to maintain, as this species tends to uproot or consume vegetation.
Uaru Compatibility Notes
Classified as mostly peaceful, the Uaru is a social species that requires the company of its own kind to thrive. When choosing tankmates, ornamental shrimp are not safe companions and boisterous or fast-moving tankmates may cause this species undue stress. Selecting tankmates that favour different water layers from the mid-level and bottom zones can help reduce competition and territorial overlap.
Who Uaru Is Actually For
Uaru is best for a fishkeeper who wants a species that can settle into a calmer community setup and can provide a keeper who can commit to a proper group of at least 4. It makes the most sense for a hobbyist who will actually build around its needs, especially driftwood.
The most common mistake is treating Uaru like any other community fish and skipping the soft sand it needs to forage safely. Another frequent problem is underestimating its social needs. A token pair or trio often behaves very differently from a real group.
Uaru Recommended Tank Sizes
Standard aquarium sizes that meet the minimum volume and length requirements for Uaru.
Frequently Asked Questions About Uaru
How big does Uaru get?
Uaru (Uaru amphiacanthoides) typically reaches a maximum adult size of approximately 25 cm. They have a compressed body shape and a moderate growth rate.
What tank size does Uaru need?
A minimum aquarium volume of 400 litres and a tank length of at least 150 cm are recommended for Uaru. This ensures enough swimming space and helps maintain stable water conditions.
What water parameters does Uaru need?
Uaru thrives in freshwater only conditions with a temperature range of 27–30°C, a pH between 5 and 7, and a general hardness of 1–8 dGH. A low water flow is preferred.
Is Uaru peaceful or aggressive?
Uaru is classified as mostly peaceful with an aggression score of 4 out of 10. They are generally well-suited to peaceful community tanks.
Can Uaru live alone?
No, Uaru should be kept in groups of at least 4 to reduce stress and encourage natural behaviour.
Is Uaru safe with shrimp?
No. Uaru is known to eat ornamental shrimp and is not recommended for shrimp tanks. Even larger shrimp species like Amano Shrimp may be at risk.
Does Uaru have any special tank requirements?
Yes. Uaru benefits from driftwood (digestion/hiding) and sand (sifters) in the aquarium. These features help replicate their natural habitat and promote overall health and well-being.
Useful setup supplies
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Guidarium Editorial Desk
Reviewed against Guidarium care, stocking, and compatibility standards. Read the editorial policy.
- Last reviewed
- April 28, 2026
- Last updated
- April 28, 2026
- Issues or corrections?
- Contact the editorial team
Top Tank Mates for Uaru
These fish are strong compatibility matches for Uaru based on water preferences, temperament, adult size, and tank behavior.
Tiger Pleco (L002)
Panaqolus sp. L002
Ideal Tank MatesStarlight Bristlenose Pleco (L183)
Ancistrus dolichopterus
Ideal Tank MatesGold Spot Pleco (L001 / L022)
Pterygoplichthys joselimaianus
Ideal Tank MatesJurupari Eartheater
Satanoperca jurupari
Ideal Tank MatesFlash Pleco (L204)
Panaqolus albomaculatus
Ideal Tank MatesStriped Raphael Catfish
Platydoras armatulus
Ideal Tank MatesPlants That Suit Uaru
These plants pair well with Uaru based on shared water preferences, layout fit, and how likely they are to hold up in the same aquarium.
Asian Watergrass
Hygroryza aristata
Asian Watermoss
Salvinia cucullata
Banana Plant
Nymphoides aquatica
Beckett's Water Trumpet
Cryptocoryne beckettii
Broad-leaved Crypt
Cryptocoryne pontederiifolia
Crypt Wendtii
Cryptocoryne wendtii
Fish Similar to Uaru
Severum
Heros severus
Severums are large, deep-bodied South American cichlids often called the 'Poor Man's Discus'. They are relatively peaceful for their size compared to other large cichlids, but they are notorious plant destroyers with a highly herbivorous diet. They require spacious aquariums with excellent filtration.
Discus
Symphysodon aequifasciatus
Known as the 'King of the Aquarium', Discus are stunning, heavily laterally-compressed cichlids. They are famous for their demanding husbandry, requiring high temperatures (28-32°C / 82-90°F), pristine water quality, and specialized diets. They are schooling fish that establish a strict pecking order and must be kept in groups to prevent intense bullying of a single weaker fish.
Blue Acara
Andinoacara pulcher
A stunning and relatively peaceful South American cichlid. While they possess classic cichlid traits—such as digging and territoriality during breeding—they are generally far more tolerant of tank mates than their larger cousins (like the Green Terror). They will, however, eagerly consume any fish small enough to fit in their mouths (like Neon Tetras).
Freshwater Angelfish
Pterophyllum scalare
The most iconic South American Cichlid, known for its distinct arrowhead shape and majestic fins. While domestic strains are hardy, they remain cichlids: they are semi-aggressive predators that will eat any fish small enough to fit in their mouths (like Neon Tetras). They form loose shoals as juveniles but pair off and become territorial as they mature. Height is more important than length for this species.
Threadfin Acara
Acarichthys heckelii
A stunning, generally peaceful South American cichlid closely related to the 'Earth-eaters' (Geophagus). They are famous for the long, trailing red filaments extending from their dorsal fins. They continuously sift substrate for food, making fine sand an absolute requirement for their gills and natural behaviors. While relatively peaceful in a community of similarly sized fish, they become fiercely territorial during breeding.
Uruguayan Eartheater
Gymnogeophagus australis
A beautiful, subtropical eartheating cichlid from the Uruguay River basin. They constantly sift sand for food and are generally peaceful but territorial during breeding. Crucially, they require a cool 'winter' period (15-20°C) to thrive long-term; keeping them at year-round tropical temperatures will drastically shorten their lifespan and cause them to lose color.